Aerohydraulic pressure autotransformer for chucks and the like



y 1966 E. TOROSSIAN 3,253,412

AEROHYDRAULIC PRESSURE AUTOTRANSFORMER FOR CHUCKS AND THE LIKE Filed Feb. 25, 1964 3 Sheets-Sheet 1 y 1, 1966 E. TOROSSIAN 3,253,412

AEROHYDRAULIC PRESSURE AUTOTRANSFORMER FOR CHUCKS AND THE LIKE Filed Feb. 25, 1964 3 Sheets-Sheet 2 May 31, 1966 AEROHYDRAULIC PRESSURE AUTOTRANSFORMER FOR Filed Feb. 25, 1964 E. TOROSSIAN 3,253,412

CHUCKS AND THE LIKE 3 Sheets-Sheet 5 United States Patent 3,253,412 AEROHYDRAULIC PRESSURE AUTOTRANS- FORMER FOR CHUCKS AND THE LIKE Edouard Torossian, Bolleystr. 50, Zurich, Switzerland Filed Feb. 25, 1964, Ser. No. 347,305 Claims priority, application Switzerland, Nov. 21, 1963, 14,272/ 63 6 Claims. (Cl. 60-545) This invention relates to an improvement in or modification of pressure intensifying devices. A device of this type is described and claimed in my copending application Serial No. 268,817. In this earlier-filed patent application the pressure intensifying device comprises a pneumatic cylinder provided with a cylinder head, a partition movable in said cylinder head forming an extensible fluid reservoir in the cylinder-head, a hydraulic cylinder mounted on said head and forming one of the acting elements of the device, a ram integral with a piston provided in said pneumatic cylinder, traversing said partition to generate high pressure in the hydraulic cylinder and a bolt integral with said pneumatic cylinder head forming the other acting element of the device.

These prior embodiments have for their object the airhydraulic control of devices with which they are attached, and thus serve for the control of this device alone.

The technical advance of the present application consists in the fact that it utilises the procedures as described in the previous application to realise a device of universal utility.

According to the present invention there is provided an air-hydraulic pressure intensifying device comprising a cylinder closed at one end and having a cylinder head at the other end thereof, a free floating piston in said cylinder displaceable between said piston head and a stop location intermediate the ends of said cylinder and defining with said cylinder head an hydraulic reservoir chamber in said cylinder, said cylinder head having an extension forming a high compression hydraulic chamber communicating with said hydraulic reservoir chamber through an opening in said cylinder head and having at least one outlet connectable to a pressure responsive means, another piston in said cylinder displaceable between said closed end of said cylinder and said stop location and defining a pair of air chambers respectively with said free floating piston member and said closed end, said other piston having a plunger extending axially through an opening in said free floating piston into said hydraulic reservoir chamber and in axial alignment with the opening in said cylinder head, said air chambers having port means for selectively supplying air under pressure thereto, whereby said free floating piston is displaceable toward said cylinder head to force hydraulic fluid from said hydraulic reservoir chamber through said high compression hydraulic chamber to a pressure responsive means connected to said outlet, and said other piston is displaceable toward said free floating piston to insert said plunger into the opening in said cylinder head for isolating said hydraulic reservoir chamber from said high compression hydraulic chamber and for highly compressing the fluid in said high compression hydraulic chamber so as to actuate said pressure responsive means.

This invention will now be described by way of example with reference to the accompanying drawing, wherein:

FIG. 1 is a multi-purpose pressure intensifying device, in longitudinal vertical section;

FIGS. 2 and 3 are respectively an end view and a plan view thereof;

FIG. 4 represents a modification in vertical section;

FIG. 5 is a horizontal section along the line X-X in FIG. 4, showing the action of the valves of the pneumatic control.

As shown in FIG. 1, a compression chamber 1 is provided within a fixed cylinder head 2 which closes an extensible reservoir 3, the latter being arranged in a cylinder 4 integral with a pneumatic cylinder 5.

A movable member 6, which is constantly urged against a shoulder 8 by a spring 7, separates the two cylinders 4 and 5.

The compression chamber 1 communicates with the reservoir3 by means of a short bore 9 which can be closed by a plunger 10 passing through the movable partition in fluid-tight manner and controlled by a pneumatic piston 11.

Moreover, the chamber 1 is arranged in a cylindrical or prismatic body 12 comprising tapped bores 13 intended to receive either the connections which will, connect the unit by means of flexible or rigid conduits to'the various devices which it will have to control, or closure plugs 14.

A lug 15 serves to secure the unit for example, upon a machine bench.

Finally a conventional distributor 16, controlled by a handle 17' and fixed above the unit, has the purpose of supplying compressed air, alternately through the channels 18 and 19, either for action upon the movable member 6 or upon the piston 11, or to relieve them of all pressure by placing the channels into connection with atmosphere.

The manner of operation is as follows: At rest, the compression chamber 1 is assumed to be connected by conduits to one or more devices for operation by the unit so that the handle 17 occupies for example the position (FIG. 3): the channels 18 and 19 are connected to atmosphere; the movable member 6 abuts the shoulder 8 and the piston 11 is at the end of the cylinder 5.

When the handle 17 is brought from the position A to the middle position A the channel 19 still remains in contact with atmosphere, but compressed air penetrates through channel 18 and, while keeping the piston 11 at the'end of the cylinder 5, acts upon the movable member 6, thereby compressing the oil contained in the reservoir 3. The compressed oil passing through the bore 9, and the chamber 1, flows into the devices to be controlled and actuates them for the purpose of providing a low-pressure clamping action.

The movement of the handle to position A reconnects channel 18 to atmosphere after the channel 19 has been placed in communication with the source of compressed air. The latter, exerting its thrust upon the pneumatic piston 11, advances the plunger 10 secured thereon, causing closure of the bore 9, and thereby isolation of the reservoir 3 from the compression chamber 1. A high pressure is therefore established in chamber 1 which will be communicated to the various devices to be controlled.

In the modification shown in axial section in FIG. 4, the pressure intensifying unit is disposed in a vertical position with the aim of receiving, on its upper part, mounted in fluid-tight manner above the compression chamber 1, a transparent element 20 constituted on the one hand by a conduit 21 of small diameter connected to the compression chamber, and on the other hand by a small auxiliary reservoir 22.

In the arrangement as represented by FIG. 4, the transparent element is fixed on the unit through the intermediary of a metallic flange 23 held by tierods 24.

A plug 25, screwed into a threaded bore 26 of the flange 23. can seal the conduit 21, while a passageway 27 keeps the auxiliary reservoir constantly in communication with atmosphere.

From the above it follows that every time the slightest infiltration of air takes place into the unit, as a result of various operations, especially during the attachment of the connection pipes, this air will accumulate in the pressure intensifying device so as to be visible in the transparent pocket formed by the conduit 21 and the plug 25, and it will be sufficient to unscrew the latter slightly in order to evacuate this air and fill up the empty space with the oil contained in the auxiliary reservoir.

A blind perforation 28 and lateral holes 29 opening into it, formed in the plug 25, permit the contents of the transparent auxiliary reservoir to be renewed, without the necessity of unscrewing the plug.

A manometer 30, connected to the chamber 1 by a fluid-tight but regulable coupling assembly, gives a con stant indication of the pressure inside the unit so that it can be remedied in the case of failure.

The tapped bores 13 formed around the compression chamber for the purpose of receiving the connection pipes intended for the control of the various devices can be of any desired size, depending on the function of the fluid delivery necessitated by each device.

In this embodiment the unit is constituted by a tubular body 32 divided by a circlip 33 into an extensible reservoir and pneumatic cylinder.

The cylinder head 2 and the base 34 are hermetically fixed by means of assembly rings 35 screwed on this tubular body.

The assembly is supported by a base 36 resting on a lug 37 intended to secure the unit on all machine or other benches.

The base 36 can contain the compressed air control distributor which actuates the transformer. For this purpose the base 36 comprises a transverse bore 38 through which there passes a rod 39 maintained by bearings 40 and carrying at its two ends two handles 41 to operate the distributor.

Two hardened cams 42 and 43, keyed on the rod, controlling respectively the actions of the movable member 6, and the pneumatic piston 11, each actuate two valves 42 42 and 43 43 which are diametrically opposed, the valves 42 and 43 being intended for the entry of compressed air which penetrates into the distributor through the common nozzle 44, while the valves 42 and 43 serve for its evacuation through a common outlet 45.

Springs 46 tend constantly to hold the valves in the closed position, while balls 47, interposed between the valves and the cams, render the distributor practically free from wear.

Moreover the impeccable operation of the distributor is ensured due to the fact that the closure of the valves is effected by the combined action of the springs and of the compressed air, guaranteeing perfect sealing and infallibility of closure.

Two networks of chamberings, perforations and identical channels 48 and 49, arranged in the base, connect respectively the valves 42 42 and 43 43 The network 48 (FIG. 4) which, under the control of the cam 42, actuates the movable partition 6, opens into an axial pipe 50 fast with the base 34, this pipe extending into a central hollow 51 formed in the plunger 10, which in turn communicates with the pneumatic cylinder by means of ports 52, while the network 49, identical in all points with the foregoing, and not shown in the drawing, under the control of the cam 43, terminates at the conduit 53 in the base, in order to actuate theoperations of the pneumaticpiston and of the plunger.

The operational cycles of the movable member and of the pneumatic piston are the same as those of the unit as described with reference to FIG. 1.

I claim:

1. An air-hydraulic pressure intensifying device comprising a cylinder having a vertical axis and a closed bottom end, a cylinder head located at the upper end of said cylinder, a free floating piston in said cylinder displaceable between said cylinder head and a stop location intermediate the ends of said cylinder and defining with said cylinder head an hydraulic reservoir chamber in said cylinder, said cylinder head having a vertical extension formed with a high compression hydraulic chamber communicating with said hydraulic reservoir chamber through an opening in said cylinder head and having at least one outlet connectable to a pressure responsive means and another outlet at the upper end thereof, air trap means connected to said other outlet and comprising a vertical tube at least partly of transparent material for detecting the accumulation of air therein, plug means for hermetically sealing an opening at the top of said tube, said plug means being actuable to vent air accumulating in said tube, and an auxiliary hydraulic reservoir communicating with said tube for filling the same with hydraulic fluid when said plug means is actuated to vent air accumulated in said tube, another piston in said cylinder displaceable between said closed end of said cylinder and said stop location and defining a pair of air chambers respectively with said free floating piston member and said closed end, said other piston having a plunger extending axially through an opening in said free floating piston into said hydraulic reservoir chamber and in axial alignment with the opening in said cylinder head, said air chambers having port means for selectively supplying air under pressure thereto, whereby said free floating piston is displaceable toward said cylinder head to force hydraulic fluid from said hydraulic reservoir chamber through said high compression hydraulic chamber to a pressure responsive means connected to said outlet, and said other piston is displaceable toward said free floating piston to insert said plunger into the opening in said cylinder head for isolating said hydraulic reservoir chamber from said high compression hydraulic chamber and for highly compressing the fluid in said high compression hydraulic chamber so as to actuate said pressure responsive means.

2. A pressure intensifying device according to claim 1 including compressed air distributor means located at the bottom end of said cylinder and communicating with said port means.

3. A pressure intensifying device according to claim 2 wherein said compressed air distributor means comprises a pair of cams, normally closed valves selectively opened by said cams for supplying compressed air to said port means, and spring means cooperating with the compressed air in said distributor for biasing said valves into closed position.

4. A pressure intensifying device according to claim 3 wherein said cams are mounted on a common shaft and control handle means secured at the ends of said shaft for manually adjusting said cams.

5. A pressure intensifying device according to claim 3 including a vertical tube extending through said bottom end of said cylinder into a blind bore formed in said plunger, said plunger being formed with at least one lateral port communicating between said blind bore and the air chamber defined by said pistons and said tube being connected at its bottom end with said compressed air distributor means whereby compressed air is distributed by said distributor means through said tube into the air chamber defined by said pistons.-

6. A pressure intensifying device according to claim 1 wherein said plug is formed with a blind bore open to the atmosphere anda lateral port communicating with said auxiliary hydraulic fluid reservoir whereby said resersaid plug.

References Cited by the Examiner UNITED STATES PATENTS Winans 6054.5 X Canpenter 60--54.5 Jackson 60-54.5 Barnhart 92169 X Hramoff 60-54.5

6 2,990,687 7/1961 McCrea 6054.5 3,059,433 10/1962 Hirsch 6054.5 3,102,453 9/1963 Brooks et a1 91-369 FOREIGN PATENTS 929,959 7/ 1947 France.

SAMUEL LEVINE, Primary Ex aminer.

ROBERT R. BUNEVICH, JULIUS E. WEST,

Examiners. 

1. AN AIR-HYDRAULIC PRESSURE INTENSIFYING DEVICE COMPRISING A CYLINDER HAVING A VERTICAL AXIS AND A CLOSED BOTTOM END, A CYLINDER HEAD LOCATED AT THE UPPER END OF SAID CYLINDER, A FREE FLOATING PISTON IN SAID CYLINDER DISPLACEABLE BETWEEN SAID CYLINDER HEAD AND A STOP LOCATION INTERMEDIATE THE ENDS OF SAID CYLINDER AND DEFINING WITH SAID CYLINDER HEAD AN HYDRAULIC RESERVOIR CHAMBER IN SAID CYLINDER, SAID CYLINDER HEAD HAVING A VERTICAL EXTENSION FORMED WITH A HIGH COMPRESSION HYDRAULIC CHAMBER COMMUNICATING WITH SAID HYDRAULIC RESERVOIR CHAMBER THROUGH AN OPENING IN SAID CYLINDER HEAD AND HAVING AT LEAST ONE OUTLET CONNECTABLE TO A PRESSURE RESPONSIVE MEANS AND ANOTHER OUTLET AT THE UPPER END THEREOF, AIR TRAP MEANS CONNECTED TO SAID OTHER OUTLET AND COMPRISING A VERTICAL TUBE AT LEAST PARTLY OF TRANSPARENT MATERIAL FOR DETECTING THE ACCUMULATION OF AIR THEREIN, PLUG MEANS FOR HERMETICALLY SEALING AN OPENING AT THE TOP OF SAID TUBE, SAID PLUG MEANS BEING ACTUABLE TO VENT AIR ACCUMULATING IN SAID TUBE, AND AN AUXILIARY HYDRAULIC RESERBOIR COMMUMICATING WITH SAID TUBE FOR FILLING THE SAME WITH HYDRAULIC FLUID WHEN SAID PLUG MEANS IS ACTUATED TO VENT AIR ACCUMULATED IN SAID TUBE, ANOTHER PISTON IN SAID CYLINDE DISPLACEABLE BETWEEN SAID CLOSED END OF SAID CYLINDER AND SAID STOP LOCATION AND DEFINING A PAIR OF AIR CHAMBERS RESPECTIVELY WITH SAID FREE FLOATING PISTON MEMBER AND SAID CLOSED END, SAID OTHER PISTON HAVING A PLUNGER EXTENDING AXIALLY THROUGH AN OPOENING IN SAID FREE FLOATING PISTON INTO SAID HYDRAULIC RESERVOIR CHAMBER AND IN AXIAL ALIGNMENT WITH THE OPENING IN SAID CYLINDER HEAD, SAID AIR CHAMBERS HAVING PORT MEANS FOR SELECTIVELY SUPPLYING AIR UNDER PRESSURE THERETO, WHEREBY SAID FREE FLOATING PISTON IS DISPLACEABLE TOWARD SAID CYLINDER HEAD TO FORCE HYDRAULIC FLUID FROM SAID HYDRAULIC RESERVOIR CHAMBER THROUGH SAID HIGH COMPRESSION HYDRAULIC CHAMBER TO A PRESSURE RESPONSIVE MEANS CONNECTED TO SAID OUTLET, AND SAID OTHER PISTON IS DISPLACEABLE TOWARD SAID FREE FLOATING PISTON TO INSERT SAID PLUNGER INTO THE OPENING IN SAID CYLINDER HEAD FOR ISOLATING SAID HYDRAULIC RESERVOIR CHAMBER FROM SAID HIGH COMPRESSION HYDRAULIC CHAMBER AND FOR HIGHLY COMPRESSING THE FLUID IN SAID HIGH COMPRESSION HYDRAULIC CHAMBER SO AS TO ACTUATE SAID PRESSURE RESPONSIVE MEANS. 